Axis History Forum

This is an apolitical forum for discussions on the Axis nations and related topics hosted by the Axis History Factbook in cooperation with Christian Ankerstjerne’s Panzerworld and Christoph Awender's WW2 day by day.
Founded in 1999.

This has a firing table of the BR-540 APHE shell with striking velocities as well as realistic time-of-flights. So this appears to have corrected values.
The ballistics of the BR-540 shell for both guns should be virtually the same except the MV of the ML-20 is 600 m/s while that of the ML-10 is 560 m/s.
The penetration values would have to be calculated from corrected striking velocities.
152mm BR-540.jpg

Mobius, I cant believe I haven't noticed this before, but that firing table is NOT for the armour piercing shell BR-540 but for the "БронеПрожигаюший"БП-540 shell aka the HEAT shell for this gun. Its mass and external ballistics are much different.

This report has a penetration table based on the DeMarre formula of the standard K=2400 type. Solving for velocity using this table gets some unbelievable numbers as well.

About that...

The ballistics for this shell are far too good for a sharp tipped shell without windshield and are much closer to BR-412B and other shells of this type than to sharp tipped shells without windscreen.
One explanation I can think of would be that they've used the ballistic model for BR-540B shell to calculate these penetration tables.

This has a firing table of the BR-540 APHE shell with striking velocities as well as realistic time-of-flights. So this appears to have corrected values.
The ballistics of the BR-540 shell for both guns should be virtually the same except the MV of the ML-20 is 600 m/s while that of the ML-10 is 560 m/s.
The penetration values would have to be calculated from corrected striking velocities.
152mm BR-540.jpg

Mobius, I cant believe I haven't noticed this before, but that firing table is NOT for the armour piercing shell BR-540 but for the "БронеПрожигаюший"БП-540 shell aka the HEAT shell for this gun. Its mass and external ballistics are much different.

I discovered that when I entered it in my ballistics program from the pdf links you provided. From a ML-10 table the MV=560 m/s BR-540 has a striking velocity of 305 m/s at 3000 m. Yet working from DeMarre the striking velocity calculated of the BR-540 from the penetration value of the ML-20 MV=600 m/s is 447 m/s at 3000 m. That is quite a big difference.

The ballistics for this shell are far too good for a sharp tipped shell without windshield and are much closer to BR-412B and other shells of this type than to sharp tipped shells without windscreen.
One explanation I can think of would be that they've used the ballistic model for BR-540B shell to calculate these penetration tables.